Sticking coefficients on a silicate surface held at 10 K obtained from the model. Thick black line for D atoms and thin black line for H atoms with T₀(D) = 50 K and T₀(H) = 25 K, respectively, and β = 2.5 (β-value for a gas phase at thermal equilibrium). Blue dashed line obtained from formulae (a) (Le Petit et al. 2006), blue short-dashed line obtained from (T/102 + 1)^-2 formulae (b) (Buch & Zhang 1991; Andersson & Wannier 1993), blue dotted line obtained from (T² × 1.0 × 10^-4 + 1)^-1 formulae (c) (Le Bourlot 2002) and red dashed line (d) from  Burke & Hollenbach (1983)’s theoretical simulations.